[hiram112]

Exactly. I was concentrating on backend the last few years and didn't have much frontend tasks. I recently switched to a new project that was developed by a generally younger team, and it's way more complex.

Instead a JSP / ASP / Rails template files with a single CSS and JS page, along with JQuery and a few libs, there is a whole build process with dependency hell and a dozen tools to master - bower, grunt, npm, karma, etc.

Writing the frontend with promises and async patterns is actually more difficult than the backend which has been slimmed down to basic Rest -> Service - DB calls. Honestly, I'd probably do pretty poorly on an interview too, these days, if a 'Ninja Full Stack' dev. was desired.